1. Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. Key Laboratory for Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, China
4. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China
5. National Astronomical Observatories, Chinese Academy of Sciences, Beijing, China
6. Centre for Astrophysics, Guangzhou University, Guangzhou 510006, China
7. Xinjiang Astronomical Observatory, Chinese Academy of Sciences, 150 Science 1-Street, Urumqi, Xinjiang 830011, China